1. FIELD OF THE INVENTION
The present invention relates to a circuit with a capacitive element and a method for testing the same.
2. DESCRIPTION OF THE RELATED ART
ICs (IC=integrated circuit) are increasingly required to integrate electronic devices, which are at present mounted outside the integrated circuit on a board. This leads to a reduction of the space requirements for a circuit, which is to perform a predetermined functionality. Thereby, increasingly, capacitors are integrated, for example, in silicon high-frequency ICs. Thus, the number of required devices in a high-frequency circuit or high-frequency system, respectively, can be reduced.
Normally, the capacitors integrated in the silicon high-frequency IC or chip, respectively, are designed such that they have a higher breakdown voltage than the semiconductors or resistor devices used in the integrated circuit.
However, the capacitors integrated in the chip can often not be provided with voltages as high as their breakdown voltage when testing the device. Thus, it is harder or impossible to detect defective capacitors. Those defective capacitors can represent a reliability risk for an operation of the integrated circuit.
This reliability risk causes a limitation of the overall size of used capacitors in an integrated circuit to a value, where a probability of a failure of one of the used capacitors remains low. This has the effect that larger capacitors are frequently mounted at the external terminals or outside the integrated circuit on a circuit board, respectively, as discrete capacitors, and are connected with those integrated circuits via their external terminals. Thus, due to the external capacitors, which are to be provided on the printed circuit board, increased space requirements result on a printed circuit board for a circuit with predetermined functionality.